Be cautious of what you post under your own name. You're not protected if your boss disagrees with you and fires you.

Employers are not similarly restricted in expressing their political views or encouraging support for a particular candidate or cause. Not only can employers remind employees of the upcoming election and encourage them to vote, but they can base continued employment on whether a worker agrees to contribute money or time to the boss’s favorite political candidate, so long as there’s no state law prohibiting it. (Eight states and the District of Columbia have laws protecting employees from such mandates.)
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Consider the case of David Siegel, founder of Orlando (Fla.)-based Westgate Resorts, the nation’s biggest time-share developer and the man behind what is planned to be the largest house in America. In February, Siegel told Bloomberg Businessweek that his efforts were largely responsible for the 2000 election of President George W. Bush. “I’m not bragging, I’m just stating the fact: I personally got George W. Bush elected,” he said. “I had my managers do a survey on every employee. If they liked Bush, we made them register to vote. But not if they liked Gore.” Siegel also said his company’s call center made 80,000 calls on behalf of Bush’s campaign.

The right to free speech is only between a citizen and the government.

The bottom line is pretty simple: Be satisfied with talk at work that doesn’t offend colleagues or anger the boss. “The Constitution operates as a restriction on government, not private employers,” Trapp says. “An employee would do well to keep this in mind before shooting off her mouth at the workplace.”